A New Palaeogeographic Model for the Post-Glacial Marine And
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A new palaeogeographic model for the post-glacial marine and estuarine sediments of the Firth of the Forth, Scotland Engineering Geology and Infrastructure Programme Open Report OR/18/038 BRITISH GEOLOGICAL SURVEY ENGINEERING Geology and Infrastructure PROGRAMME INTERNAL REPORT IR/18/038 A new palaeogeographic model for the post-glacial marine and estuarine sediments of the Firth of The National Grid and other the Forth, Scotland Ordnance Survey data © Crown Copyright and database rights 2018. Ordnance Survey Licence No. 100021290 EUL. R Palamakumbura Keywords Firth of the Forth; Post-glacial Contributor/editor sediments; Devensian; Younger Dryas; Claret Formation; Errol T Kearsey, M Krabbendam, A Finlayson, K Whitbread, S Arkley Clay Formation. Front cover Geovisionary image of the Firth of Forth with BGS 1:50 000- scale superficial geology map overlain. Bibliographical reference R PALAMAKUMBURA 2018. A new palaeogeographic model for the post-glacial marine and estuarine sediments of the Firth of the Forth, Scotland. British Geological Survey Open Report, OR/18/016. 49pp. Copyright in materials derived from the British Geological Survey’s work is owned by UK Research and Innovation (UKRI) and/or the authority that commissioned the work. You may not copy or adapt this publication without first obtaining permission. Contact the BGS Intellectual Property Rights Section, British Geological Survey, Keyworth, e-mail [email protected]. You may quote extracts of a reasonable length without prior permission, provided a full acknowledgement is given of the source of the extract. Maps and diagrams in this book use topography based on Ordnance Survey mapping. © UKRI 2018. All rights reserved Keyworth, Nottingham British Geological Survey 2018 BRITISH GEOLOGICAL SURVEY The full range of our publications is available from BGS British Geological Survey offices shops at Nottingham, Edinburgh, London and Cardiff (Welsh publications only) see contact details below or shop online at Environmental Science Centre, Keyworth, Nottingham www.geologyshop.com NG12 5GG The London Information Office also maintains a reference Tel 0115 936 3100 collection of BGS publications, including maps, for consultation. BGS Central Enquiries Desk We publish an annual catalogue of our maps and other publications; this catalogue is available online or from any of the BGS shops. Tel 0115 936 3143 email [email protected] The British Geological Survey carries out the geological survey of Great Britain and Northern Ireland (the latter as an agency service BGS Sales for the government of Northern Ireland), and of the surrounding continental shelf, as well as basic research projects. It also Tel 0115 936 3241 undertakes programmes of technical aid in geology in developing email [email protected] countries. The Lyell Centre, Research Avenue South, Edinburgh The British Geological Survey is a component body of UK Research EH14 4AP and Innovation. Tel 0131 667 1000 email [email protected] Natural History Museum, Cromwell Road, London SW7 5BD Tel 020 7589 4090 Tel 020 7942 5344/45 email [email protected] Cardiff University, Main Building, Park Place, Cardiff CF10 3AT Tel 029 2167 4280 Maclean Building, Crowmarsh Gifford, Wallingford OX10 8BB Tel 01491 838800 Geological Survey of Northern Ireland, Department of Enterprise, Trade & Investment, Dundonald House, Upper Newtownards Road, Ballymiscaw, Belfast, BT4 3SB Tel 01232 666595 www.bgs.ac.uk/gsni/ Natural Environment Research Council, Polaris House, North Star Avenue, Swindon SN2 1EU Tel 01793 411500 Fax 01793 411501 www.nerc.ac.uk UK Research and Innovation, Polaris House, Swindon SN2 1FL Tel 01793 444000 www.ukri.org Website www.bgs.ac.uk Shop online at www.geologyshop.com Contents Contents ........................................................................................................................................... i Summary ....................................................................................................................................... iv 1 Introduction ............................................................................................................................ 5 1.1 Rationale ......................................................................................................................... 5 1.2 Testable hypothesis......................................................................................................... 5 1.3 Geological Event model of the Firth of Forth ................................................................ 6 2 Methods and data ................................................................................................................... 8 2.1 Mapped Devensian raised marine deposits .................................................................... 8 2.2 Shoreline mapping arc .................................................................................................... 8 2.3 BGS Groundhog ............................................................................................................. 9 3 Cross section results ............................................................................................................. 10 3.1 Forth Road Bridge ........................................................................................................ 10 3.2 Rosyth ........................................................................................................................... 13 3.3 Bo’ness ......................................................................................................................... 15 3.4 Grangemouth ................................................................................................................ 18 3.5 Skinflats ........................................................................................................................ 20 3.6 Plean ............................................................................................................................. 23 3.7 Chartershall ................................................................................................................... 26 3.8 Stirling .......................................................................................................................... 28 3.9 South-West of Doune ................................................................................................... 31 4 Discussion of the major features and deposits ................................................................... 34 4.1 Sea-level record in the Forth ........................................................................................ 34 4.2 subsurface rockhead topography .................................................................................. 34 4.3 Glacial deposits............................................................................................................. 34 4.4 Devensian raised marine deposits................................................................................. 35 4.5 Main Perth Shoreline .................................................................................................... 36 4.6 Post glacial estuarine infill ........................................................................................... 36 4.7 Bothkennar Gravel ........................................................................................................ 37 4.8 Holocene raised marine deposits and beach deposits ................................................... 38 4.9 Main Post-glacial shoreline .......................................................................................... 38 5 Depositional model of the Firth of the Forth ..................................................................... 39 6 Further work and applications ........................................................................................... 42 7 Conclusions ........................................................................................................................... 43 References .................................................................................................................................... 44 i FIGURES Figure 1. Overview maps of the Firth of Forth showing the mapped Devensian raised marine deposited and the interpreted Devensian Palaeocoastline. In addition, cross section lines are shown, that later described including at the: 1) Forth Road Bridge, 2) Rosyth, 3) Bo’ness, 4) Grangemouth, 5) Skinflats, 6) Plean, 7) Chartershall, 8) Stirling, and 9) South-west of Doune........................................................................................................................................ 8 Figure 2. Geological map of the raised marine superficial deposits and interpreted Devensian palaeo-coastline at the Forth Road Bridge ............................................................................. 10 Figure 3. GeoVisionary image of the small hill near the Forth Road Bridge, comprising Till, surrounded by Devensian raised marine deposits. .................................................................. 11 Figure 4. Groundhog section through the small till hill to the west of the Forth Road Bridge (Figure 2) (Vertical exaggeration is 10x). Borehole records used for interpretations are marked by the vertical lines with associated BGS borehole ID number. ............................... 11 Figure 5. BGS Groundhog cross section showing the continuous upper silt bed near the Forth Road Bridge. Borehole records used for interpretations are